**3. General climatic and agronomic conditions of wine regions in China**

According to administrative division and the meteorological and geographical regionalization, China wine producing regions have been widely categorized into 11 recognized regions [6], including the Northeast, the Eastern Region of Helan Mountain, Beijing-Tianjin-Hebei (also known as Jing-Jin-Ji), Shandong (also known as Jiaodong Peninsula), Old Course of the Yellow River, Loess Plateau, Inner Mongolia, Hexi Corridor, Southwest Alpine, Xinjiang and Others (**Figure 2**).

As can be seen from **Figure 2**, viticulture and enology are widely distributed in China, from 24 to 47°N, 76–132°E. The majority of vineyards are located in northern China, where they are affected by the continental monsoon climate with cold, dry winters and extremely low temperatures of 15°C during the winter. The fatal flaw for grape varieties is not only extremely low temperatures but also large amounts of water evaporation caused by extreme droughts in spring and winter, often known as 'drought-freezing'. As a result, measures have been adopted to protect vines from the cold and drought during the winter months. One of the most effective methods is to bury the vine in the soil, which is also known as buried viticulture.

In addition, some sub-areas in China's south and southwest have been identified as wine producing regions. These regions are generally located at a high altitude with a complex ecological condition, also suitable for the cultivation of *Vitis vinifera* species. However, the most planted grapes are traditional Chinese varieties such as *Vitis quinquangularis* and *Vitis heyneana* as well as their hybrid varieties (**Table 2**). The detailed information of China wine production regions, including the location, latitude & longitude, vineyard area (kha), main variety, wine production volume (mhl), meteorology, climatic subdivisions, altitude (m), and agrotype are shown in **Table 2**.

#### **Figure 2.**

*Chinese wine production regions.*

The vineyard area for wine grape in each region can be seen from **Table 2**, with a total of 163.39 kha, however, the CADA report (2018) shows that the wine grape area in China was only 85.19 kha, which could be due to some table grapes that are also used for winemaking being counted in **Table 2**.

In China, the main cultivated grape varieties in most regions are similar. The red grape varieties play a dominant role which occupies more than 80% [3], and among them, Cabernet Sauvignon is the most widely planted variety, followed by Merlot and Cabernet Gernischt (**Table 2**).

Recently, a new red variety, *Vitis vinifera* L.cv. Marselan, which was bred in 1961 by the French National Institute for Agricultural Research (INRA), and introduced in China in 2001, showed good adaptability in China and was considered a new star variety in China wine regions. The parent variety of Marselan is two famous red grape varieties, Grenache and Cabernet Sauvignon. Wines made from Marselan showed both parent characters, with medium-bodied and fine tannins, good color, intense fruity aroma presented in cherry and cassis flavor [8]. Nowadays, Marselan is being planted in Hebei, Shandong, Xinjiang, Ningxia, and Gansu Regions. Some wineries made wines from the single or blended Marselan variety and won lots of important awards. According to some domestic experts, Marselan wine is well suited for Chinese consumers and could be a very potent variety in China.

White grape varieties only represent a small quantity of about 20% in China. Among them, Chardonnay, Italian Riesling, and Riesling are the commonly cultivated varieties in the various regions (**Table 2**). A traditional white grape variety known as Longyan, has the potential to be utilized as both a table grape and a wine grape. As a late-harvested variety, the Longyan grape has been widely cultivated in

